Storage-battery plate and process of making same



' ing to the capacit of the given capacity ma es a considerable amount RUFUS N- CHAMBERLAIN, OF CHICAGO, ILLINOIS, ASSIGNOR TO GOULD STORAGE BATTERY COMPANY, A CORPORATION OF NEW YORK.

STORAGE-BATTERY PLATE AND PROCESS OI MAKING SAME.

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Specification of Letters Patent.

Patented May 31, 1921.

No Drawing. continuation of application Serial No. 214,663, filed January 31, 1918. This application Y filed September 12 1918. Serial No. 253,806.

To all whom it may concern Be it known that I, RUFUS N. CHAMBER- LAIN, a citizen of the United States, and a resident of the city of Chicago, county of Cook, State of Illinois, have invented certain new and useful Im rovements in'Storage-Battery Plates and rocesses of Making Same, of which'the following is a specification.

My invention relates to storage batteries and one of the objects of my invention is to increase the capacity of a plate of given dimensions while at the same time materially decrease the weight thereof. Considerable investigation has been made heretofore in an endeavor to increase the surface of active material which comes in contact with electrolyte in storage battery plates of the pasted type with a view to increasing the ef'ficiency of the battery.

It is well known that there is a considerable amount of active material in the plates of ordinary construction which 'is not effective probably because the electrolyte does not have suficient access to the interior thereof. Practically. speaking, this extra weight of active material, which might be called inert or inactive, not only adds nothplate, but for a of undesirable weight.

Due to the rapid development of automobiles and submarines it has become of great. importance to decrease the weight of storage batteries as well as to increase the capacity thereof per unit of weight.

By my present invention I solve this problem and produce a late having the desired qualities. This p ate is produced by mixing finely divided porous material with the active material or material to become active. I have found the following method of manufacture of such plates commercial but it is understood that my invention is not limited to this precise method of manufacture.

The lead oxid, active material or material to become active, is mixed with finely divided wood particles or similar absorbent material, the roportion of wood articles, if that material is used, bein a out one part by'volume to four parts 0 :OXIC l. or active material b volume. The wood particles or equiva ent acid abs r ent is Drefin a well known way. When wood' particles are used, I prefer to use a wood which has l1ttle or no organic acid forming material therein, such as for instance California red wood or cypress. I have found these two woods to be satisfactory although other woods may be used. In anyvevent the wood or other particles should preferabl be used 1n a highly divided state. I pre er to use particles none of which is so large that it will not ass through a screen of 30 mesh. The pre erred range. in size is 25 to 40 mesh but variations may be made and beneficial results obtained, but I have found that the best results are obtained with particles not larger than 25 mesh. When wood parchargeby, increasing its capacity. Later when the active material becomes softer and more porous and more absorbent, due to service conditions, the absorbent material by that time may have partially lost its texture .ments. of the active material during disand body and given way to the more expanded and porous active material. I have found that the absorbent material aids the active material in its acid qualities when this is most needed, that is when the plate is new, and this aiding in the acid qualities decreases when the necessit therefor has partially or substantially dlsappeared, that is after the plate has een in service for a period of time. I have found that if the particles used are large the active material of theplate will be weakened mechanically .and that way the life of the plate will be shortened. One advantage therefore of the finely divided particles is that the plate is strong mechanically. 'Another is that of increased capacity, per unit weight.

' .rate'd. It also By the use of small particles as above described, many advantages are secured over plates in which fibers or pulp or other material of stringy nature have been incorpohas many advantages over a plate in which any material, which, when wet, forms lumps or is non-uniform. The advantages secured, as above indicated, consist of a strong mechanical structure, a uniform active material, long life and a uniform increase of capacity throughout the whole of the active material of the plate.

ll do not know exactly what takes place, nor exactly how the benefits derived are secured but ofi'er by way of suggestion the following possible explanation,- to wit The absorbent material makes it possible for little pockets of acid to be uniformly distributed throughout the body of the active material whereby a large'part of the active material in the plate may be used effectively and efiiciently, as distinguished from the mere surface contact as used heretofore. As the plate continues in service the absorbent material probably deteriorates and allows the active material through expansion to become more porous and absorbent itself, this porosity coming from serviceconditions and the same being permitted by the presence of these specks of deteriorated absorbent material, which are also elastic.

I desire not to be limited in any respect to the explanation above outlined, but ofier the same merely as my opinion.

Resulting from the invention above disclosed the capacity of the plates is increased from twenty to thirty per cent. over the ordinary pasted plates, and the weight of the active material of this plate of twenty per 'cent. increased capacity is fifteen to thirty per cent. less than the active material revaeoo of the regular pasted plate of the same di mensions.

While l have given above, as an example, the proportions of absorbent material to be used and the preferred size and range of mesh to the inch and the quantity of wood particles present in the active material being about 1 part wood to 4: parts by volume of active material when dry.

2. The method of making'a storage battery plate which consists in mixing about 1 part of wood particles containing relatively little organic acid, with about a parts by weight of active'battery material, the wood particles being of a size to ass through a screen of about 30 mesh, ma 'ng a paste of the mixture and pasting the same on to a battery grid. v

3. A. storage battery plate comprising a said activev material having uniformly distributed therein particles of wood containing relatively little organic acid, the particles of wood being mostly of a size that will pass through a screen of about 30 mesh.

In testimony whereof, ll have signed my name to this specification. Y

RUFUS N. CHAMBERLAIN.

- grid with active materlal pasted thereon, 

